This invention relates generally to opto-electronics and more specifically to interconnection of opto-electronic components.
Traditional high speed computer and communications systems are often built using a backplane assembly. The system is built on several printed circuit boards, called xe2x80x9cdaughter boardsxe2x80x9d, that are interconnected through a backplane.
A traditional backplane is a printed circuit board that has many signal traces running through it. The traces route signals between connectors mounted on a surface of the backplane. The daughter cards have mating connectors along one edge, allowing each daughter card to be plugged into the backplane. In this configuration, the daughter cards are parallel to each other and mounted at right angles to the backplane.
There are several advantages to a backplane assembly in which daughter cards are mounted at right angles to the backplane using connectors. For example, the daughter cards can be easily accessed and removed from the assembly. As a result, such systems can be easily assembled. And, a daughter card can be easily removed and replaced, to make repairs to the system or to upgrade the system.
More recently, electronic systems have needed to transmit more data than could be reliably transmitted in electrical form. Some high speed systems are now being built with transmission paths that represent signals using light beams. Data can be transmitted at a very high rate using light beams. Instead of metal traces, such systems use optical fiber or waveguides built into circuit boards to transmit the light.
To connect boards in a right angle, a fiber bundle is typically used. The fiber is bent into a right angle. However, there are several drawbacks to using fiber bundles to connect boards at a right angle to create a backplane assembly. One difficulty is that fiber has a limited bend radius. Consequently, extra space is taken up by the fibers. In addition, having fibers running between boards creates a potential failure point and therefore the reliability of the system is decreased.
With the foregoing background in mind, it is an object of the invention to provide an electro-optical assembly that is easily manufactured and reliable.
The foregoing and other objects are achieved through the use of a substrate carrying a waveguide to a via hole. A reflector is positioned in the hole to redirect a light beam traveling through the waveguide to the desired direction.
The substrate is manufactured by positioning the reflector in a hole and adjusting its position based on amount of light transmitted through it. In a preferred embodiment, the light used to position the reflector is generated internal to the substrate, such as by a phosphorescent material.